Codec: . Add ?c=vp9 to the URL for the VP9 variant.

The delay readout is server time of each frame vs. this browser's clock, so it assumes both clocks are NTP-synced. It includes ~0.2 s of encoder startup and buffer.

Read the white clock burned into the video and compare it with the DOM clock. The difference is the video path delay. Take a screenshot with both visible.